diff --git a/src/test_stylesheet.py b/src/test_stylesheet.py
new file mode 100644
index 0000000..d30a0df
--- /dev/null
+++ b/src/test_stylesheet.py
@@ -0,0 +1,74 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+from mapcss import MapCSS
+import mapcss.webcolors
+whatever_to_hex = mapcss.webcolors.webcolors.whatever_to_hex
+import sys
+
+reload(sys)
+sys.setdefaultencoding("utf-8")
+
+minzoom = 0
+maxzoom = 18
+
+style = MapCSS(minzoom, maxzoom)
+style.parse(open(sys.argv[1],"r").read(), clamp=False)
+TOTAL_TESTS = 0
+FAILED_TESTS = 0
+
+def compare_zoom(a, function, b):
+    "a is over b on all zooms"
+    global TOTAL_TESTS, FAILED_TESTS
+    for zoom in range(minzoom, maxzoom+1):
+        for typ1 in ['line', 'node', 'area']:
+          for typ2 in ['line', 'node', 'area']:
+            sa = [x.get('z-index', 0.) for x in style.get_style(typ1, a, zoom)]
+            sb = [x.get('z-index', 0.) for x in style.get_style(typ2, b, zoom)]
+            if sa and sb:
+                la = min(sa)
+                lb = max(sb)
+                TOTAL_TESTS += 1
+                if la < lb:
+                    print "BAD: z%s\t[%s %s %s %s %s]\t[%s, %s], " % (zoom,typ1,la,function, typ2,lb, repr(a), repr(b))
+                    FAILED_TESTS += 1
+
+
+
+compare_zoom({'area:highway': 'primary'},   "over", {'highway': 'primary'})
+
+compare_zoom({'highway': 'primary'},        "over", {'waterway': 'river'})
+compare_zoom({'highway': 'path'},           "over", {'waterway': 'river'})
+
+
+compare_zoom({"highway": "motorway"},       "over", {'highway': 'primary'})
+compare_zoom({"highway": "motorway_link"},  "over", {'highway': 'primary_link'})
+compare_zoom({"highway": "trunk"},          "over", {'highway': 'primary'})
+compare_zoom({"highway": "trunk_link"},     "over", {'highway': 'primary_link'})
+compare_zoom({'highway': 'primary'},        "over", {'highway': 'secondary'})
+compare_zoom({'highway': 'primary_link'},   "over", {'highway': 'secondary_link'})
+compare_zoom({'highway': 'secondary'},      "over", {'highway': 'tertiary'})
+compare_zoom({'highway': 'secondary_link'}, "over", {'highway': 'tertiary_link'})
+compare_zoom({'highway': 'tertiary'},       "over", {'highway': 'residential'})
+compare_zoom({'highway': 'tertiary'},       "over", {'highway': 'service'})
+compare_zoom({'highway': 'tertiary'},       "over", {'highway': 'unclassified'})
+compare_zoom({'highway': 'tertiary'},       "over", {"highway": "living_street"})
+compare_zoom({'highway': 'tertiary'},       "over", {"highway": "road"})
+compare_zoom({'highway': 'residential'},    "over", {'highway': "track"})
+compare_zoom({'highway': 'residential'},    "over", {'highway': "service"})
+compare_zoom({'highway': 'unclassified'},   "over", {'highway': "track"})
+compare_zoom({'highway': 'track'},          "over", {'highway': "path"})
+compare_zoom({"highway": "steps"},          "over", {'highway': "pedestrian"})
+compare_zoom({"highway": "steps"},          "over", {'highway': "footway"})
+compare_zoom({"highway": "steps"},          "over", {'highway': "cycleway"})
+compare_zoom({"highway": "cycleway"},       "over", {'highway': "footway"})
+
+
+compare_zoom({"amenity": "bank"},           "over", {'amenity': "atm"})
+compare_zoom({"amenity": "bank"},           "over", {'amenity': "atm"})
+compare_zoom({"railway": "station"},        "over", {'leisure': "park"})
+
+
+
+print "Failed tests: %s (%s%%)" % (FAILED_TESTS, 100*FAILED_TESTS/TOTAL_TESTS)
+print "Passed tests:", TOTAL_TESTS - FAILED_TESTS
+print "Total tests:", TOTAL_TESTS
\ No newline at end of file